Method and apparatus for synchronizing an Email client on a portable computer system with an Email client on a desktop computer

ABSTRACT

A fully integrated email system for a desktop computer with an associated palmtop computer is disclosed. The portable computer has an email client for viewing incoming email messages and composing outgoing email messages. The personal computer has an email synchronization conduit that synchronizes email on the portable computer email client with email for the desktop computer system. The email synchronization conduit ensures that the email state on the portable computer system matches the email state on the desktop personal computer system exactly. Thus, if an email message is deleted on the portable computer system then that email message will be deleted from the desktop personal computer system. Similarly, if an email message is deleted on the desktop personal computer system then that email message will be deleted from the portable computer system.

FIELD OF THE INVENTION

The present invention relates to the field of portable computerssystems. Specifically, the present invention discloses a systems forsynchronizing an email client on a portable computer system with anemail client on a desktop computer system.

BACKGROUND OF THE INVENTION

Personal computer systems have become common tools in modern society.One of the most important uses for personal computers is electronic mail(email). Personal computer users use email to send notes and computerfiles to other computer users.

Many personal computer users also use small portable palmtop computersystems such that the personal computer user can carry importantpersonal information. To store the important personal information,palmtop computer systems usually provide Personal Information Management(PIM) applications such as an address book, a daily organizer, and aTo-Do list applications.

In addition to the Personal Information Management (PIM) applications,it would be desirable to have an email application on the palmtopcomputer system. The email application would allow the user to send andreceive email messages using the palmtop computer system.

Although an email application on palmtop computer system would be veryuseful, such an application can create problems. For example, wouldincoming email arrive on the desktop personal computer system, theportable computer system or both? Furthermore, if the user deleted anemail message on one of the two computer systems, should that emailmessage appear on the other computer system? Thus, it would be desirableto have an email application for a palmtop computer system that iscompletely in synchronization with an email application on a desktoppersonal computer system.

SUMMARY AND OBJECTS OF THE INVENTION

It is therefore an object of the present invention to provide a palmtopcomputer system that is fully integrated with common email systems usedby desktop personal computers. To accomplish this goal, the presentinvention introduces an email client for the portable computer systemand an email synchronization conduit for a desktop personal computersystem.

The email client for the portable computer system allows the user toview incoming email messages. The email client on the portable computersystem also allows the user to compose outgoing email messages.

The email synchronization conduit on the desktop personal computersystem is responsible for synchronizing the state of the portablecomputer email client with an email client on a personal computersystem. After a synchronization event, the email synchronization conduitensures that the email state on the portable computer system exactlymatches the email state on the desktop personal computer system. Forexample, if an email message is deleted on email client of the portablecomputer system then a matching copy of that email message will bedeleted from the desktop personal computer system. Similarly, if anemail message is deleted on the email client of the desktop personalcomputer system then that email message will be deleted from theportable computer system. By keeping the email state of the twodifferent computer systems in exact synchronization, the user can switchbetween the email client on the portable computer system and the emailclient on the desktop personal computer system without missing a messageor reading a redundant message.

BRIEF DESCRIPTION OF THE DRAWINGS

The objects, features, and advantages of the present invention will beapparent from the following detailed description of the preferredembodiment of the invention with references to the following drawings.

FIG. 1a illustrates a portable computer system and a personal computersystem equipped with a cradle for synchronizing with the portablecomputer system.

FIG. 1b illustrates a block diagram that depicts the softwarearchitecture for synchronizing information on the portable computersystem with information on a desktop personal computer system.

FIG. 2a illustrates a block diagram that depicts the softwarearchitecture for synchronizing email on the portable computer systemwith email on the desktop personal computer system using the Microsoft®MAPI protocol.

FIG. 2b illustrates a block diagram that depicts the softwarearchitecture for synchronizing email on the portable computer systemwith email on the desktop personal computer system using the Lotus® VIMprotocol.

FIG. 3 illustrates a flow diagram that describes how email on thedesktop personal computer system is synchronized with email on theportable computer system.

DETAILED DESCRIPTION

Methods and apparatus for implementing a palmtop computer system that iswell integrated with a personal computer system is disclosed. In thefollowing description, for purposes of explanation, specificnomenclature is set forth to provide a thorough understanding of thepresent invention. However, it will be apparent to one skilled in theart that these specific details are not required to practice the presentinvention. In other instances, well-known circuits and devices are shownin block diagram form to avoid obscuring the present invention.

Basic Synchronization

FIG. 1a illustrates a portable computer system 130 that communicates andsynchronizes information with a personal computer system 110. Tosynchronize the information in the two computer systems, a user placesthe portable computer system 130 into the cradle 120 and pressessynchronization button 125. The synchronization button 125 activates asynchronization program on the portable computer system 130. Thesynchronization program on the portable computer system 130 communicateswith a peer synchronization program on the personal computer system 110.The two synchronization programs synchronize the information on the twocomputer systems.

FIG. 1b illustrates a block diagram of the software components thatperform the synchronization of the two computer systems. In FIG. 1b, theportable computer 160 has two different programs, program A and programB, that execute on the portable computer 160. Program A and program Buse a common database 163 to store their data.

Referring to FIG. 1b, a synchronization cradle 180 is illustrated belowthe portable computer 160. The synchronization cradle 180 has a button185 that activates a synchronization Program (HotSync) 161 in theportable computer system 160. When activated, the HotSync Program 161communicates with the peer synchronization program (HotSync Manager) 170in the personal computer 150. The HotSync Manager 170 operates byexecuting a series of conduit programs such as conduit program A andconduit program B illustrated in FIG. 1b. Each conduit program is usedto synchronize the information associated with a particular program onthe portable computer system. Conduit programs can also performadditional tasks such as software installation. A full description ofthe synchronization architecture can be found in U.S. Pat. No. 5,727,202entitled “Method and Apparatus for Synchronizing Multiple Files On TwoDifferent Computer Systems”.

In FIG. 1b, conduit program A and conduit program B are used tosynchronize the data for application program A and application program Bon the portable computer 160 respectively. The HotSync Manager 170communicates with the HotSync Program 161 in order to access thedatabase 163 on the portable computer 160. The necessary records from ofthe database 163 are copied to the personal computer such that theconduit programs on the personal computer can process the records. Inthe example of FIG. 1b, the records from database 163 that areassociated with application program A and application program B arecopied into the personal computer and then reconciled with databases Aand database B by conduit A and conduit B respectively. After therecords have been synchronized, the synchronized records are writtenback to the database 163 on the portable computer system 160.

Email Synchronization

Synchronizing email information is not as simple as synchronizing asimple database such as an address list. To fully describe how thepresent invention synchronizes an email client program on a desktoppersonal computer system with an email client program on a portablecomputer system, a detailed description is provided with reference toFIGS. 2a, 2 b, and 3.

FIG. 2a illustrates the general software architecture for synchronizingan email client program on a desktop personal computer system with anemail client program on a portable computer system. In the example ofFIG. 2a, the email client program on the personal computer uses theMicrosoft MAPI protocol. However, other email protocols may also be usedas will be described later.

FIG. 2a illustrates a portable computer system 210 having an emailclient program 211. The email client program 211 works with emailrecords stored in the database 215. The email client program 211 allowsthe user to view received email stored in the database 215. The emailclient program 211 also allows the user to compose new email messages tobe sent to other computer users.

The portable computer system requires a connection to a computer networkinfrastructure to receive new email and to send newly composed emailmessages. To connect with the computer network infrastructure, thisdocument describes a synchronization environment wherein the portablecomputer is coupled to a personal computer using a serial link asdepicted in FIGS. 1a, 1 b, and 2 a. However, many other methods ofconnecting the portable computer system to a personal computer system asdescribed in the patent application “Method And Apparatus PorSynchronizing A Portable Computer System With A Desktop Computer System”filed on Jan. 30, 1997 with Ser. No. 08/792,166, now U.S. Pat. No.6,006,274.

To update the email records stored in database 215, the user can placethe portable computer system 210 into a cradle coupled to a personalcomputer through a serial link. The user presses a syncrhonizationbutton on the cradle to activate a HotSync Program 217 on the portablecomputer system 210. The HotSync Program 217 on the portable computersystem 210 communicates through the serial link with a HotSync ManagerProgram 231 on the personal computer system. The HotSync Manager Program231 executes a number of conduit programs to synchronize databasesincluding an email conduit program 233 to synchronize the emailinformation.

To synchronize the email records from the portable computer system, theemail conduit 233 communicates with a MAPI software layer 253 in theoperating system software of the personal computer 250. The MAPIsoftware layer 253 provides a limited set of routines for manipulatingemail on an email server. Detailed information about the MAPI softwarelayer can be found in the Microsoft Developer Network documentspublished by the Microsoft Corporation.

Referring to FIG. 2a, a MAPI-compliant email server 280 is connected toa computer network 270 that is also coupled to the personal computersystem 250. One MAPI-compliant email server is the Microsoft (MS)Exchanger Server illustrated in FIG. 2a. To access the email informationon the MAPI-compliant email server 280, an application program on thepersonal computer 250 can issue MAPI compliant requests to the MAPIsoftware layer 253. The MAPI software layer 253 transmits a requestpacket across the computer network 270 to the MAPI compliant emailserver 280. In response to the properly formatted MAPI requests, theMAPI-compliant email server 280 sends information back to the MAPIsoftware layer 253.

For example, the Microsoft Mail email client program 240 on the personalcomputer system can send and receive email by issuing requests to theMAPI software layer 253. The MAPI software layer 253 transmits therequests through the appropriate network software to the MAPI-compliantemail server software 281 on a server 280. The MAPI-compliant emailserver software responds through the network 270 back to the MAPI layerand thus back to the mail client software 240.

To send and received email, the email conduit 233 uses the sameinfrastructure. Thus, the email conduit 233 also makes requests to theMAPI software layer 253. The MAPI software layer 253 transmits therequests from the email conduit 233 through the appropriate networksoftware to the MAPI-compliant email server software 281 on server 280.

It should be noted that the email server software 281 on server 280maintains the email “state” for each user that the email serverservices. Specifically, the email server software maintains a set ofactive email messages for each user. By communicating through the MAPIsoftware layer 253, the email conduit 233 can synchronize the emailrecords on the portable computer system 210 with the email informationon email server software 281 on server 280.

FIG. 3 illustrates a flow diagram that describes how the email clientconduit 233 on the personal computer system 250 synchronizes the emailstate on the portable computer system 210 and the personal computersystem 250. First, at step 310, the email conduit 233 retrieves all theoutgoing email from the portable computer system 210. This outgoingemail is sent to the email server software 281 using MAPI commands suchthat the outgoing email is sent to the desired recipient. At step 315,the email conduit determines if the user has selected a “send-only”mode. The send-only mode allows the user to shorten synchronizationsessions by only sending outgoing email. If the user has selected thesend-only mode the email client is done and stops at step 317. Otherwisethe email conduit continues to synchronize the email in database 215with the email on the email server software 281.

At step 320, the email conduit 233 reads all the email for the user fromthe email server 281. If the email conduit 233 cannot read the emailfrom the server then the conduit will terminate since it cannot obtainthe information necessary for the synchronization. After reading all theemail from the email server 281 the email conduit 233 then reads all theemail stored in the database 215 in the portable computer system at step330.

At step 335, the email conduit 233 checks to see if this is asynchronization with the same personal computer that was used to performthe previous synchronization. If this is the same personal computer,then the email from the portable computer system will have valid statusflags that specify the new, changed and deleted email from the portablecomputer system. However, if this is not the same personal computer thatwas used in the previous synchronization then the conduit proceeds tostep 337 where it compares the email from the portable computer systemwith the email from the last synchronization to determine the new,changed and deleted email from the portable computer system. Additionalinformation about the system of using a state from a previoussynchronization is available in U.S. Pat. No. 5,727,202 entitled “Methodand Apparatus for Synchronizing Multiple Files On Two Different ComputerSystems” with Ser. No. 08/544,927, filed on Oct. 18, 1995, now U.S. Pat.No. 5,727,202.

Next, at step 340, the email from the email server 281 is compared withthe email retrieved from the portable to determine the new, changed anddeleted email from the email server 281. After this step the email thatis new, changed or deleted from the email server 281 is available.

The final step is then to synchronize the email information from theemail server 281 and the email information from the portable computersystem. To accomplish this goal, the email conduit 233 uses the list ofthe new, changed and deleted email from the portable computer system andthe list of the new, changed and deleted email from the email server281. Specifically, the list of the new, changed and deleted email fromthe portable computer system is used to modify the email on the emailserver 281 and the list of the new, changed and deleted email from theemail server 281 is used to modify the email information on the portablecomputer system. Thus, at step 350, if an email message has been deletedfrom the email server 281 then that email message is deleted from theemail list on the portable computer system. Similarly, if an emailmessage has been deleted from the portable computer system then thatcomputer system. If an email message has been modified on either systemthen that email message is modified on the other system. For example, ifemail has been marked as read on either system then the email is markedas read on the other system. Finally, if new email has been received bythe email server 281, then that new email is copied into the database inthe portable computer system.

The techniques illustrated with reference to the MAPI based email systemof FIG. 2a can be used in other email systems. For example, FIG. 2billustrates a similar mail arrangement. In FIG. 2b, the server 280 isrunning the Lotus® cc:mail server software 283 on the server 280. Tocommunicate with the Lotus® cc:mail server software, a VIM softwarelayer 257 is placed in the system software of the personal computersystem 250. The VIM software layer 257 is used by the Lotus® cc:mailclient program 242. Since the VIM and MAPI software layers are verysimilar, the same method described in FIG. 3 can be used to synchronizeemail on systems use the VIM protocol.

Although the present invention has been described in terms of specificexemplary embodiments, it will be appreciated that various modificationsand alterations might be made by those skilled in the art withoutdeparting from the spirit and scope of the invention as set forth in thefollowing claims.

What is claimed is:
 1. A computer implemented method of synchronizingemail between multiple computers, the method comprising: reading a firstset of messages from a portable computer into a first personal computer;identifying an outgoing message in the first set of messages to bedelivered from the first personal computer to a mail server; identifyingon the first personal computer a second set of messages previouslyretrieved from a server, the second set of messages having, at leastonce prior to a previous event, a first message that matched acorresponding message in the first set of messages; comparing the firstset of messages with the second set of messages to identify if at leastthe corresponding message in the first set of messages that matched thefirst message in the second set of messages was deleted or modifiedafter the previous event; and automatically signaling the outgoingmessage to the mail server.
 2. The method of claim 1, wherein the secondset of messages include flags to identify whether each message in thesecond set of messages was added to or deleted from the second set ofmessages since a previous event.
 3. The method of claim 1, furthercomprising identifying if any messages in the second set of messageswere modified on the first personal computer after the previous event,then replacing select messages in the first set of messages with themodified messages.
 4. The method of claim 1, further comprising causingthe first message in the second set of messages to be deleted from thesecond set of messages if the corresponding message has been deletedfrom the first set of messages since the previous event.
 5. The methodof claim 1, further comprising causing the first message in the secondset of messages to be modified if the corresponding message has beenmodified on the portable computer since the previous event.
 6. Themethod of claim 1, further comprising comparing the first set ofmessages to the second set of messages to identify if the second set ofmessages includes at least a first new message added to the second setof messages after the previous event.
 7. The method of claim 6, furthercomprising adding the first new message to the first set of messages,then signaling the first set of messages to the portable computer. 8.The method of claim 1, further comprising signaling the first set ofmessages to the portable computer after comparing the first set ofmessages and the second set of messages.